why does my baxi 105e keep going over 3 bar and losing water l?

hi
difficult to say without looking at it but i would have to say maybe your filling loop is faulty or slightly open if the kids have got to it or maybe even a pet has knocked it.
filling loop is the pipe (usually a flexi pipe) that goes from your main supply to your cold supply to the boiler.
worth a look
gaz

gary
May 2008